I recently put a 3.4L ohv (PR) engine in my Fiero GT '87 Aut.
The engine is new and stock with the standard cam, 17lb injectors ,sinister chip, fiero store heat coated sprint manifold/y-pipe and ocelot exhaust and no cat.
The waterdeflector in the wheelwell has been removed and a pipe has been installed instead.
The lower/middle/upper intake has been glass blasted inside/outside to improve air flow.
My fiero runs great with the new engine, but it feels like it "stops pulling" when it reaches 4000-4500rpm.
I have read that to the stock intake does not deliver enough air for the 3.4L ohv.
That particular modified stock intake will flow enough air to make ~200 HP. That's about where Chuck (fierochild) was with his 3.4. He had a 272 cam and some other stuff. Think his heads may have been ported too. That being the case, it should work fine with yours. (The 4500 "wall" is well known with 3.4 installs using the stock intake.)
I have a Trueleo on mine, but my engine has nearly as many mods as Chucks. The Trueleo will be a lot less trouble than modifying the stocker. It will flow more than the heads will, even ported.
------------------ Raydar 88 4.9 Formula IMSA Fasback..........................88 3.4 coupe -soon to be something other than red Read Nealz Nuze!Praise the Lowered!
[This message has been edited by Raydar (edited 01-23-2010).]
I have not modified my stock 2.8 manifold plenum because it is a chore to do it right .. the gains are small unless you get it correct..I have 30 projects before this you should port match and install a glass pac or a muffler that flows more freely,,opening up the 2.8 exhaust system is the best easy way to improve performance, you have to be willing to go a bit louder
KEEP THE STOCK AIR INTAKE ,with minor improvements..up to the TBI,,The manifold is a choke point,,modifications to areas before the TBI & where it mounts are choked off,, you have to port the manifold/plenum,,then port match Porting the heads will not yield good gains unless the manifold is opened up.. The truleo is the only way to go for performance these are my thoughts from observation,,not backed up by much intake experience
[This message has been edited by uhlanstan (edited 01-23-2010).]
I agree with Uhlanstan. I have the 390 cfm carb and my little 2.8 is still climbing at 6200 rpm. I don't have the gonads to push it higher but I am sure it will go. The heads are ported and the stock cam has 1.6 rockers.
I did the carb conversion before I heard about Trueleo. If I was doing it again I would likely go with Trueleo. That said, there is nothing wrong with the carb conversion either. It is totally reliable and goes like stink.
Not trying to hijack this thread but, I'm curious if anyone has any actual supporting cfm numbers of reductions?
I'm going to be looking at this on my flowbench in the very near future as I get an intake tract setup for a future 3.4 engine swap. I've accumulated all the parts except the airbox/hose/inlet. First thing will be to flow everything in stock form and see where the reductions are at. Why am I doing this you might ask? Simply because I want to "play", I have the flowbench and it's all about learning something new.
I think it comes down to what you are after for your car? Putting a large intake will suit for high rpm HP but if you are looking for a fun car to drive on backroads do you really need an intake that will flow more air than the heads can support? Is the "4500 wall" caused by the upper intake or somewhere else?
I've read a lot of thoughts on this subject using the search here but have not found any actual flow numbers.
I think i will start to modify my spare stock intake and see if helps for the "4500 wall"
I will start by dyno my Fiero with the stock intake and then compare it with the modified intake.
Think the truleo intake is a bit pricy for me when i live in Denmark, compared to the gains i am going to get (if ordered i need to pay import taxes and vat. and total price with shipping ends up arrond 950-1000$) :-(
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09:31 AM
TiredGXP Member
Posts: 712 From: A cold, miserable place Registered: Jan 2008
Not trying to hijack this thread but, I'm curious if anyone has any actual supporting cfm numbers of reductions?
I'm going to be looking at this on my flowbench in the very near future as I get an intake tract setup for a future 3.4 engine swap. I've accumulated all the parts except the airbox/hose/inlet. First thing will be to flow everything in stock form and see where the reductions are at. Why am I doing this you might ask? Simply because I want to "play", I have the flowbench and it's all about learning something new.
I think it comes down to what you are after for your car? Putting a large intake will suit for high rpm HP but if you are looking for a fun car to drive on backroads do you really need an intake that will flow more air than the heads can support? Is the "4500 wall" caused by the upper intake or somewhere else?
I've read a lot of thoughts on this subject using the search here but have not found any actual flow numbers.
This sounds like a terriffic piece of research. Will you start a thread with your results/conclusions?
I too have a 3.4L with all the goodies and I've been thinking also about trying to improve the stock intake. Trying to keep the stock look, cut the intake horizontally as close to the bottom as possible and to were the downward portions are almost vertical.... Insert some sort of walls that were the stock perimeter shape of the intake. CNCed maybe since the wall thickness is about 1.8" and make it like a cookie cutter and we raise the top shell about 3/4" for flow. Welded in place and grinded to look stock instead of a garage project... Basically making the top intake fatter vertically.
Has anyone tried that?
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10:36 PM
Jan 25th, 2010
Pyrthian Member
Posts: 29569 From: Detroit, MI Registered: Jul 2002
I've done it - and it is ALOT of work and, it is now cracking along the welds
being I have done a 7730 & have DIS, I will ditch my "improved" intake for a 3.4 Camaro Intake.
making the larger neck sections was so damn fussy. it is not easy to make the multiple compound curves required to do the neck. overall - if you are going to do this - do it like WCF did - remove the whole damn neck, and re-weld a new neck w/TB flange on, and be done with it. dont try and re-create & match the existing curves.
[This message has been edited by Pyrthian (edited 01-25-2010).]
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09:21 AM
82-T/A [At Work] Member
Posts: 22896 From: Florida USA Registered: Aug 2002
I've been thinking about this for a long time too.. I noticed a HUGE drop at 4,000rpms when I did my 3.2 rebuild. (3.1 crank / rods w/ .040 overbore pistons).
I've thought about doing what Pyrthian did too...
There's another option, but I can't really think about how beneficial it would be. Extrude-Honing. Based on all the research I've done on the internet, it really is a hit or miss. For some vehicles, it makes a substantial difference. For others, it makes very little difference. I've never seen an instance where it HURT performance.
For those who don't know what it is, it's basically they send an abrasive material coarsing through the intake manifold where it smooths out the entire intake passage.
The only problem is... on our Fieros, you'd end up paying close to $1,000 bucks to have it done. This is because they do it by number of components and to do it right, you'd want to send in the plenum, runners, and the intake manifold.
They would bolt something up to where the throttle body bolts to, and then they would install plates at the intake so it doesn't destroy the port openings. Then, they send the stuff through, and it not only polishes the entire intake, but also smooths it out eliminating any bumps. It DOES actually increase the CFM of the entire intake simply because all of the ports get enlarged through the process. This includes the NECK. As I said, they protect the opening and exit with special plates to prevent those openings from enlarging.
Like I said, I've NEVER done this, but I've done a bunch of research on the internet from it. If I had to hazard a guess, I would say that you WOULD see a subtantial benefit, but I don't think it would eliminate completely "the wall" that we experience at 4,500 rpms. I would guess you'd get some better flow, probably see an improvement to 5,100 or something (pure non-scientific guess). You can only enlarge the neck so much before it simply NEEDS more metal than can be reasonably removed.
What it WILL do however, is automatically port-match everything for you... like the inconsistencies between the plenum and the runners (which isn't so bad) and the inconsistencies between the runners and the intake manifold (which are attrocious).
I'm still thinking about doing it on my Fiero because... honestly... I have to realize that my Fiero is NOT a V8 Fiero, and it's not my goal to make it a 370Z killer... I just want it to be quick, sporty, and fun... like it always was. I just have to decide if $1,000 bucks is worth spending on that kind of improvement. But for me, I want to keep the factory Fiero intake.
when I was port matching my intakes, one of my ideas was to get them sanding sponges and a string/chain get the sanding sponge mounted in the middle of the length of string/chain then force it into the port/runner, and then pulling it back & forth thru the runner
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12:57 PM
82-T/A [At Work] Member
Posts: 22896 From: Florida USA Registered: Aug 2002
when I was port matching my intakes, one of my ideas was to get them sanding sponges and a string/chain get the sanding sponge mounted in the middle of the length of string/chain then force it into the port/runner, and then pulling it back & forth thru the runner
I was also trying to think of something along that same principal. Did you ever end up doing it? How did it work out for you?
Extrude Hone removes material from where "it wants to" not where it might need to be removed from.
Port velocities need to be considered not just overall cfm.
While that may true, we know for a fact that the bottleneck in the Fiero's intake is the neck. I would assume though that where this material would remove would be the same places that air is disturbed in the intake too.
I got a quote for $910 from the guy who runs sales. I know it sounds crazy, but I think it's something I'm going to consider. I've already done some port-matching and whatnot... but I think I'll definitely do some extra work on the pieces before I send it out. I might even try to do some work on the neck too... not sure yet.
Originally posted by Brucepts: Extrude Hone removes material from where "it wants to" not where it might need to be removed from.
Port velocities need to be considered not just overall cfm.
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Originally posted by 82-T/A [At Work]: While that may true, we know for a fact that the bottleneck in the Fiero's intake is the neck. I would assume though that where this material would remove would be the same places that air is disturbed in the intake too.
There is more than one bottleneck, so it may be more accurate to say, "One of the bottlenecks in the Fiero's intake manifold is the neck."
Remember that the runners of the stock intake manifold also force intake air to make some 90o turns, a path that is not conducive to higher-RPM power production, nor are intake runners that probably are too long for higher-RPM power production in the first place. I don't see how extrude honing can be expected to successfully eliminate 90o bends or make the runners shorter.
quote
Originally posted by 82-T/A [At Work]: I got a quote for $910 from the guy who runs sales. I know it sounds crazy, but I think it's something I'm going to consider.
In regard to your comment about "crazy," I once saw somewhere a definition of insanity which asserted that pursuing the same action while expecting a different outcome exemplifies insanity. One might argue, however, that you are not insane because now, you are not pursuing the same action. More specifically, now you would have to pay $160 more for extrude honing than you would have had to pay when in 2005 you posted the comment below (quoted from your 2005 thread, "Improving Stock Intake Plenum" https://www.fiero.nl/forum/Forum2/HTML/069539.html ):
quote
Originally posted by 82-T/A [At Work]: ... I e-mailed the guy at Extrude Hone.... he wants $750 dollars to do the three-piece intake. He would send the extrude-hone material through the opening of the intake plenum, and pass it down through the runners, and out through the lower intake manifold.
I think your project will prove more challenging than you've anticipated, but nonetheless (and all kidding aside), I wish you the best of luck with it.
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08:04 PM
PFF
System Bot
topher_time Member
Posts: 3231 From: Bailey's Harbor, for now. Registered: Sep 2005
Originally posted by project34: There is more than one bottleneck, so it may be more accurate to say, "One of the bottlenecks in the Fiero's intake manifold is the neck."
Remember that the runners of the stock intake manifold also force intake air to make some 90o turns, a path that is not conducive to higher-RPM power production, nor are intake runners that probably are too long for higher-RPM power production in the first place. I don't see how extrude honing can be expected to successfully eliminate 90o bends or make the runners shorter.
yup - another is the EGR port it is right behind the throttle body, and the shape of the port creates quite a tornado - which reduces the flow past it. when I bored by TB to 57mm, I also filled in the EGR port w/epoxy and smoothed it.
the Stock Fiero Plenum restrictions: EGR port, the neck near the main body, the length of the runners & the tight curves of the runners there is also the multiple peices, which create the mating areas - the overall design, where the runners meet at such a horrible angle between the lower plenum & intake manifold
also, if you look at the intake manifold itself - you'll see a 5-15% restriction right at the port. and looking further up, you'll see the injector bung could use some clean-up as well.
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09:18 AM
82-T/A [At Work] Member
Posts: 22896 From: Florida USA Registered: Aug 2002
I think your project will prove more challenging than you've anticipated, but nonetheless (and all kidding aside), I wish you the best of luck with it.
I don't want to hijack the thread, but a lot of people have a hard time understanding that I want my car to LOOK stock.
If I was overly concerned with break-neck speed... I would find some way to drop my 1969 Olds 455 Big Block into my Fiero.
I just want to get the best flow out of my Fiero's intake setup, while maintaining a nearly 100% stock look.
My goal is really just to get into the 14s with this car, that's it.
I have to work within the confines of the stock intake components, but I should be able to make an appreciable difference with proper porting. I'm not expecting a 40 horsepower increase or something. But if I can get another 10-15hp from what I would otherwise expect from a stock intake and a 3.2 rebuild, then I would be really happy.
yup - another is the EGR port it is right behind the throttle body, and the shape of the port creates quite a tornado - which reduces the flow past it. when I bored by TB to 57mm, I also filled in the EGR port w/epoxy and smoothed it.
the Stock Fiero Plenum restrictions: EGR port, the neck near the main body, the length of the runners & the tight curves of the runners there is also the multiple peices, which create the mating areas - the overall design, where the runners meet at such a horrible angle between the lower plenum & intake manifold
also, if you look at the intake manifold itself - you'll see a 5-15% restriction right at the port. and looking further up, you'll see the injector bung could use some clean-up as well.
Yeah, like we talked about in an earlier thread (or maybe this one), the factory port-matching between the runners and intake manifold were HORRIBLE. In some cases, I found as much as a 3/8ths restriction between two overlapping ports... it was BAD.
Originally posted by 82-T/A [At Work]: I don't want to hijack the thread, but a lot of people have a hard time understanding that I want my car to LOOK stock....I just want to get the best flow out of my Fiero's intake setup, while maintaining a nearly 100% stock look.
To clarify matters, I didn't suggest a Trueleo or a dual-plenum intake manifold for you here because I think you've been quite clear in the past about wanting to maintain "a nearly 100% stock look." My point was only that by working within that constraint...
quote
Originally posted by project34: I think your project will prove more challenging than you've anticipated, but nonetheless (and all kidding aside), I wish you the best of luck with it.
My guess is a similar caveat also would apply to the originator of the present thread, FieroGT_DK, because of the interest he's expressed in modifying the stock Fiero intake manifold --- albeit not for the appearance-related purposes you've mentioned, but because of the amount of import tax in Denmark he'd need to pay on a U.S.-made Trueleo intake manifold.
quote
Originally posted by Arns85GT: If you just want 14's with nothing spectacular on a daily basis, button it up and put nitrous on it. A 75 shot should put you into the 14's.
Arn
That nitrous suggestion relates to another interesting issue in regard to what you've mentioned, 82-T/A [At Work]. What constitutes "a nearly 100% stock look"? A readily visible nitrous bottle in the trunk doesn't do that for me, but a well-concealed nitrous bottle somewhere might. Yet another viewpoint on a different thread was that somebody felt a 3800 SC engine swap looks perfectly stock to those who aren't familiar with Fieros.
I thought that to be a HUGE stretch of the imagination in the context of "a nearly 100% stock look," but that reminds me: FieroGT_DK, how are you able to even consider a Trueleo intake manifold for your Fiero in Denmark? Wouldn't emissions inspectors reject it because it doesn't look anywhere near stock --- or, because I assume there are precious few Fieros in Denmark, is it that emissions inspectors in Denmark wouldn't know what a stock Fiero intake manifold would look like anyway --- or is there some other reason that you've not mentioned the Trueleo's very non-stock appearance as being a disadvantage in Denmark?
I thought that to be a HUGE stretch of the imagination in the context of "a nearly 100% stock look," but that reminds me: FieroGT_DK, how are you able to even consider a Trueleo intake manifold for your Fiero in Denmark? Wouldn't emissions inspectors reject it because it doesn't look anywhere near stock --- or, because I assume there are precious few Fieros in Denmark, is it that emissions inspectors in Denmark wouldn't know what a stock Fiero intake manifold would look like anyway --- or is there some other reason that you've not mentioned the Trueleo's very non-stock appearance as being a disadvantage in Denmark?
Emission inspection regarding the Trueleo intake is not a problem they dont know what is stock, there are only approx. 15-25 registred Fiero''s in Denmark.
A Trueleo intake would in my oppinion be the best or easiest soloution for getting more air to my 3.4L, if it was made in Europe i would by one...
Stock / non stock compared to more HP ? Difficult question..., i would choose more HP
[This message has been edited by FieroGT_DK (edited 01-27-2010).]
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06:06 PM
PFF
System Bot
Jan 28th, 2010
82-T/A [At Work] Member
Posts: 22896 From: Florida USA Registered: Aug 2002
To clarify matters, I didn't suggest a Trueleo or a dual-plenum intake manifold for you here because I think you've been quite clear in the past about wanting to maintain "a nearly 100% stock look." My point was only that by working within that constraint...
I'm desperately trying not to hijack this thread... but it's like walking down the street and a hot girl uncovers herself and says... go ahead... give a squeeze. You really have to think about it...
Yeah, the nitrous idea doesn't work so much for me either. I've really taken this to a ridiuclous level. So much in fact that I painted my aftermarket Accel ignition coil with black engine paint so it matched the factory one. I even painted (using black engine paint) my yellow 17# Accel injectors so they too looked stock.
I realize I have a nearly impossible road ahead, but I think very few people have actually taken it to the degree that I'd like to.
What I actually intend to do as well, is to detail the porting and port-matching process. There are still a lot of Fieros that people pick up from time to time that are totally stock. Young kids like I was once when I first got my Fiero. A lot of these guys want to improve performance, and with the exception of gaskets, you can pretty much significantly improve the flow of the motor on an otherwise stock Fiero.
One thing I noticed is... the "wall" that 3.1-3.4 owners notice, is almost completely unnoticeable on a stock displacement motor. It's amazing how significantly it affects you when you've increased the volume demand.
Everything else being stock, I can see that from the intake standpoint, the biggest bottleneck is the neck. Nothing else is really a bottle neck until that's resolved. Of course, I'm speaking purely from a non-scientific / seat of the pants point of view. Seeing how all the pieces go together though, Pontiac spent little time finessing the match. The match between teh runners and intake are awful.
Off the top of my head, some of the things I'm hoping to do is:
1 - Increase the volume of the neck by lowering the floor. I may try to do something with the EGR opening as well, but not sure how to tackle that. I'm not going to eliminate it, but I'd like to see what porting / polishing I can do that will help the flow around the opening.
2 - I'm going to try to round-out the curve between the runners and the plenum. They basically do make 90 degree angles, but if there's some way that I can round it out some, that would work well... I just don't have a clue how that would be possible... even if I cut into it.
3 - I'm going to try to smooth out the area where the intake manifold and the runners meet. I've already port matched them years ago, but I'd like to try to create a more natural curve rather than just rounding down the area and a simple port match. This looks like it should be a bit easier.
4 - I intend to polish (to the best of my ability everything UP TO the point at which the injectors enter the intake. I had read somewhere that the disruptive surface does actually help fuel atomization... but who knows. This could be accomplished by doing the Extrude-Hone. As you know... I've been thinking about this for a while, but I only recently started working on my Fiero again (like a month ago). It's pretty much been sitting for the past 7 years in my garage.
So, that's my plan... we'll see how it turns out. I already have a 57mm throttle body with a port-match from Darrel Morse... I had that done a while ago. So I know at least THAT will never be a bottle neck.
I got my modified stock intake to flow for 185 rwhp...still hit a 4200rpm wall though. It is for sale (upper and matched middle piece w/Darrel Morse 57mmTB) for $200. It is shortened 3/4" so you will need shorter intake bolts or have the stock ones threaded farther. I may have by bots somewhere...
I have switched to a Trueleo but I don't have the car tuned yet as it came with multiple misses in the welds that caused vacuum leaks. Wish they would have pressure tested it before shipping it to me... I had the TB mounting flange set up the the L98 twin 48mm TB and that was fine but the EGR opening was left on (I asked for no EGR 3 times in emails) it and it also unfortunately takes the stock path on the neck around the distributor when I asked the that to be ignored because I was in the process of the '7730 conversion w/DIS...
Because of the nature of where my TB sits, I haven't created a proper intake tube to the air filter yet as the opening almost hits the stock trunk hinge. However, it did make connecting the the v6 throttle cable easier. :/
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10:02 AM
82-T/A [At Work] Member
Posts: 22896 From: Florida USA Registered: Aug 2002
I got my modified stock intake to flow for 185 rwhp...still hit a 4200rpm wall though. It is for sale (upper and matched middle piece w/Darrel Morse 57mmTB) for $200. It is shortened 3/4" so you will need shorter intake bolts or have the stock ones threaded farther. I may have by bots somewhere...
I have switched to a Trueleo but I don't have the car tuned yet as it came with multiple misses in the welds that caused vacuum leaks. Wish they would have pressure tested it before shipping it to me... I had the TB mounting flange set up the the L98 twin 48mm TB and that was fine but the EGR opening was left on (I asked for no EGR 3 times in emails) it and it also unfortunately takes the stock path on the neck around the distributor when I asked the that to be ignored because I was in the process of the '7730 conversion w/DIS...
Because of the nature of where my TB sits, I haven't created a proper intake tube to the air filter yet as the opening almost hits the stock trunk hinge. However, it did make connecting the the v6 throttle cable easier. :/
That's actually pretty good. 185rwhp is what, like 220-225 engine dyno horsepower? You're using a better engine to start, 3400 w/ roller cam (from what I saw in your thread).
I might be interested, can you send me some more pictures of what you did?
EDIT: I just looked again at some of the pictures, it's a little bit too modified for my taste. I think it'll have an affect on all the other things like where the throttle body sits, etc. Good work though! Thanks!!!
Originally posted by 82-T/A [At Work]: What I actually intend to do as well, is to detail the porting and port-matching process.
Do you have access to a flowbench?
How are you going to quantify the flow changes?
Do you understand what level of testing really needs to be done to do actual porting work? A lot more than just grinding away that is for sure. What you think might look/feel right is not always what the air thinks is right. Please don't take this as me being a "butthead" asking these ???'s it is not my intent . . .
Personally, I started on this venture on my flowbench over the weekend and now have a stock TB and upper intake hooked up and was playing with it on Wednesday. My long-term plan is to also do a little wetflow testing as I research a design adaptable to my flowbench. I'm planning on documenting my process as I go and will start a new thread here as well as post the info on my own website for discussion with my flowbench community. They seem to like a challenge
I know a lot of work has been done with the 2.8L intake already and is well documented on here and it is interesting reading. I'm doing this for myself to learn and as a hobby. I'm not looking for gobs of power but some good low end torque would do me fine on those backroads. I've been in a 3800SC (Skitimes) and it was fun but way out of my budget so I'm going to dabble with a 2.8L to 3.4L conversion sometime down the road.
This however will not be a weekend project and could take a few months as I have really no time schedule for completion.
Extrude hone is the way to go ..but when I looked in the intake manifold ,no way can you achieveany real gains I do not know crap about Fieros,,but have 40 years motorooter head experience mostly on racing scooters.. $900.oo?? ya gotta want it bad..
The Ford motor company was the first really big name to use extrude hone ,,it was superior to every thing else because you got uniformity,,IT works ,,just my arrogant snooty opinion that it is not worth the money for the bottleneck swoozh chamber the stock fiero Has ,$900.00??...I like many others WANT the stock neato jet manifold ,,SLICK LOOKING (adds 20 bench race horsepower) The truleo produce the horse power ,but appearence wise the 2.8 needs a good header that is close to the stock look (I can dream,right??) the outlet pipes would stick out futher (noA/C)with a more gradual sweep My car has very few modifications but it pulls to 5000rpm,strong, I never go higher,, do not have the money to pull engine apart..I seldom go over 4500rpm.. The performance is in the HEAD,flow bench porting, match the free flowingest exhaust you can get past the Law My car pulls hard because I have a glasspack which is just a straight thru pipe with slots on the side to baffle sound.. FORD used extrude hone on the late 90,s SVT escort and SVT contour made a big performance difference. and they got improved gas milage..
I was looking under the hood of my sisterinlaw's Corolla this morning and the intake is essentially a header in reverse. Nice mandrell bent pipes coming from a collector box which is attached to a filter box. Very slick... FOR AN ECONO BOX....!! So why don't we take a look at Trueleo again? Very slick. Why try to rework the stock plenum? It won't keep up even with extrude honing. It can't. The geometry won't let it.
This isn't an advertisement for Francis T, but it is a realistic look at the two intakes. From an aesthetic point of view, the stock intake is a little better IMHO. From a functional point of view, there really is no comparison.
Just my .02
Arn
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12:18 PM
82-T/A [At Work] Member
Posts: 22896 From: Florida USA Registered: Aug 2002
Do you understand what level of testing really needs to be done to do actual porting work? A lot more than just grinding away that is for sure. What you think might look/feel right is not always what the air thinks is right. Please don't take this as me being a "butthead" asking these ???'s it is not my intent . . .
No, I definitely to not have equipment like that, however, enough work and research has already been done on this forum for me to know what needs to be done. Other than port-matching (which is pretty self explanitory), everything I need to know about what restrictions exist are already well documented on here. The research has been done for me, I just need to do it. For the most part I, I just hope to go back and spend more time with it.
Extrude-Hone is pretty much the way to go to polish and port the entire intake and increase the flow as much as possible without cutting the intake pieces.
quote
Originally posted by Brucepts: I know a lot of work has been done with the 2.8L intake already and is well documented on here and it is interesting reading. I'm doing this for myself to learn and as a hobby. I'm not looking for gobs of power but some good low end torque would do me fine on those backroads. I've been in a 3800SC (Skitimes) and it was fun but way out of my budget so I'm going to dabble with a 2.8L to 3.4L conversion sometime down the road..
I tossed around the idea of the 3.4 for a while, but I figured out eventually that I could get the same power by going with a higher compression 3.2 rebuild. .040 overbore pistons with a 3.1 crank and rod configuration. I ended up with an unapproximate 9.2:1 compression ratio (based on what I was told by ARI Racing who sold me the specific kit).
I originally went with 19lb injectors (based on some advice I got on here), but then eventually went to 17lb injectors since I could literally smell the gasoline in the air. It was running SO rich. It had plenty of power though, even with my modest Th-125 GX3 transmission. I had installed a 4 cyl torque converter that was rated at a 150 higher stall than what came with it, so that helped a bit.
I started to develop some problems with timing and the car started to run poorly. With work and everything else, I ended up parking the car and it's sat in my garage for 7 years. I'm, only now getting back to it.
By the way, if you decide to go the 3.4 route... I'd be happy to loan you my 3.4 starter JIG that I bought from Rodney. Otherwise if you want your own, you can get it fairly cheap from him.
That's actually pretty good. 185rwhp is what, like 220-225 engine dyno horsepower? You're using a better engine to start, 3400 w/ roller cam (from what I saw in your thread).
I might be interested, can you send me some more pictures of what you did?
EDIT: I just looked again at some of the pictures, it's a little bit too modified for my taste. I think it'll have an affect on all the other things like where the throttle body sits, etc. Good work though! Thanks!!!
I don't know how much shortening helped but it was just the material where the upper and middle intakes meet...about .7" worth combined. Lots of smoothening after a port job as well.
Originally posted by Arns85GT: So why don't we take a look at Trueleo again? Very slick. Why try to rework the stock plenum? It won't keep up even with extrude honing. It can't. The geometry won't let it.
I don't think it likely that 82-T/A [At Work] would revisit the Trueleo. He stated he wants "a nearly 100% stock look" and while explaining that in a later post, he also stated:
quote
Originally posted by 82-T/A [At Work]: ...I painted my aftermarket Accel ignition coil with black engine paint so it matched the factory one. I even painted (using black engine paint) my yellow 17# Accel injectors so they too looked stock.
Given his comments (and hopefully this will help represent your position more well here, 82-T/A [At Work]), his definition of "a nearly 100% stock look" seems to go beyond what "100% stock" might or could look like if the factory had done things differently, but what "100% stock" actually did look like when the engine came off the factory's assembly line.
Accordingly, because a Trueleo intake is so inconsistent with his 100%-stock-appearance objective, I wouldn't be surprised if, after his reading your comment about revisiting the Trueleo intake ---espevcially if he read it just after repainting his yellow Accel injectors black so they'll look stock --- 82-T/A [At Work] now is seeking medical treatment for doing this:
On the other hand, given that the originator of this thread, FieroGT_DK, is much less concerned about "a nearly 100% stock look," he seems to be in a much better position to heed your suggestion to take another look at getting the Trueleo intake, and I'd also encourage him to do that.
